UUID generator · Guide
UUID v4 Explained
UUID v4 is the random variant, the most common in everyday use. Here is what its structure means.
Mostly random bits
A v4 UUID fills most of its 128 bits with random data, reserving a few bits to mark the version (4) and variant. That is why every v4 value looks different and collisions are negligible.
Format
It is written as 32 hexadecimal digits in five hyphen-separated groups (8-4-4-4-12). The third group starts with a 4, identifying the version.
Frequently asked questions
Can I use this for production work?
Yes, for inspection, formatting and quick generation. Still review the output before committing it to production code or configuration.
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